Ok, so what would be a natural reaction for one (any) of your dogs if someone came up behind it and startled it?
I don't know if Alfie and Tilly are strange dogs because if this happened to them they would probably jump but then they would turn around and then start wagging their tails at whoever it was had startled them. I have never heard either of them growl, it is just totally not in the nature of either of them. It doesn't seem to ever occur to them in any circumstance. I don't generally put them in situations where they will be grabbed etc. but when I was at home at Christmas my Stepbrother (who is 23!) came up behind Tilly when she was totally engrossed in looking out of the window and grabbed her around her 'waist' ... she jumped a bit then turned around and started doing her whole body wiggles while trying to lick his face.
I'm not saying this to look 'superior' in any way, and I don't really think it's anything to do with my training as I didn't get Tilly until she was 2. I'm just stating 100% honestly how it is with them and it is simply not in their nature to growl or show aggression. It's just their personalities and all are different as people are. Anyone who has met them will confirm that they are in no way cowed or submissive dogs, quite the opposite!
I can also say that the two of Cazzie's dogs I have met, Sweep and Belle, are very sweet natured but happy, lively and outgoing dogs also.
ETA: Just to clarify, Tilly had never met my stepbrother when he grabbed her, he'd just walked in the door. He is only ever at my Mum and Stepdad's house at Christmas so to her he was a complete stranger.